Effect of Li Addition on Synthesis of Mg-Ti BCC Alloys by means of Ball Milling

Abstract

The effect of Li addition to Mg on synthesis of Mg-Ti BCC alloys by means of ball milling was studied. Mg–x at%Li (x=4,20,46) alloys prepared by the induction melting method consisted of the HCP phase (Mg-type), the HCP phase + the BCC phase (Li-type) and the BCC phase, respectively. Lattice parameters of the HCP phase decreased with the increase in x, whereas those of the BCC phase at x=20 and 46 were smaller than that of Li. Mg–x at%Li (x=4,20,46) alloys and Ti were milled for 50–200 h in an argon atmosphere. Formation of Mg₉₆Li₄Ti₁₀₀ BCC alloy was confirmed by X-ray diffraction (XRD) measurements after 50 h milling. By Li addition to Mg, the synthesis time of the BCC phase was shortened. Li made Mg deformation facile by the activation of the non-basal slips in Mg, and raw materials were efficiently milled. The crystallite size of Ti was readily reduced and formation of the BCC phase was accelerated. The crystallite size and lattice parameter of Mg₉₆Li₄Ti₁₀₀ BCC alloy were similar to those of Mg₁₀₀Ti₁₀₀ BCC alloy.